Low
S.01 on Heatline Vizo 28

Your boiler is currently performing a required safety check by running its internal fan before attempting to light the flame.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Pre-run fan

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

S.02View →S.03View →

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